Comment

Comment by fsckboy

>regenerative braking on the new trains is generating and sending back to the electric grid approximately 23% of the energy consumed by the system

does this make sense? let's round that 23 up to 25%, and say brake energy regeneration is 100% efficient (it's not): one quarter of the energy put into the system comes back out? city driving in a car, you might have your foot on the brake 25% of the time (yes, that's not how it works, just think conceptually) but a train spends a lot of time running, and comparatively a small amount of time braking, and if you were to detach the engine from the train, one doesn't get a sense the train would roll very far unpowered, so while there's momentum to scavenge, it doesn't seem like 25% of the total

I'm just thinking, how do these numbers make sense?

parent fsckboy 1 year ago

Discussion

Live from the official Hacker News API

A modern reader for Hacker News · SvelteKit + Skeleton